"BorgWarner is proud to equip BMW's latest M Performance engine with the first three-stage turbocharging system for diesel engines in the world," said Frederic Lissalde, President and General Manager, BorgWarner Turbo Systems Passenger Car Products. "Driven to lead the next breakthroughs in advanced powertrain technologies, BorgWarner is once again setting new benchmarks for maximum performance combined with improved fuel economy and reduced emissions."

BorgWarner's powerful turbocharging system consists of two small BV45 high-pressure variable turbine geometry turbochargers integrated with one larger B2 low-pressure water-cooled turbocharger. By integrating an additional high-pressure turbocharger, the engine's capability to generate boost pressure reaches a completely new level compared with two-stage turbocharging systems. The three turbochargers are activated successively at different engine speeds. The first high-pressure turbocharger starts at engine speeds just above idle. With increasing revs, the larger low-pressure turbocharger comes into play. To further increase performance, the second high-pressure stage turbocharger comes on line as well with all three turbochargers working in harmony. For effective and efficient boost pressure, the exhaust flow and the supply of fresh air is regulated with maximum precision. At particularly high speeds of the low-pressure turbocharger, the wastegate valve is opened by a vacuum actuator to avoid backpressure, while pneumatically activated flaps precisely control the supply of fresh air. Indirect charge air cooling optimizes the compressed air temperature in all three turbochargers to increase engine output.